The Messenger of Allah (s) called for me and commissioned me to Yemen so that I may restore harmony between them. So, I said: O Messenger of Allah! They are a large, old community, while I am a young man. So, he said: O `Ali! Once you reach the highest site, then call at the top of your voice: “O trees! O stones! O land! Muhammad the Messenger of Allah recites the salaam to you.” He said: So, I went. When I reached the highest site, the people of Yemen came toward me yielding spears, led by their elders and priests, bearing their weapons. So, I called at the top of my voice: O trees! O stones! O land! Muhammad the Messenger of Allah recites the salaam to you. He said: There was not a tree, a stone, nor a piece of land except that it reverberated in one voice: “Peace be unto Muhammad the Messenger of Allah and you.” The feet and the knees of the people buckled, and their weapons fell from their hands. Then, they came quickly toward me; so I reconciled between them and I left.